nanog mailing list archives
Re: NTP question
From: Mel Beckman <mel () beckman org>
Date: Thu, 2 May 2019 03:30:03 +0000
Yo Gary! Not only did I not sleep through it, I was one of the engineers who verified that every GPS clock source in a very large aviation support network didn’t have have this bug. I’m also an FAA licensed A&P mechanic, and have worked for airlines in fleet maintenance. Air carriers have extremely thorough systems reviews, by law, through the Airworthiness Directive program, which started identifying 2019 GPS rollover vulnerabilities in ... 2009! Nobody was surprised. If any GPS systems “went nuts”, it was through the incompetence and negligence of their owners. -mel
On May 1, 2019, at 8:03 PM, Gary E. Miller <gem () rellim com> wrote: Yo Mel! On Thu, 2 May 2019 02:54:25 +0000 Mel Beckman <mel () beckman org> wrote:Why? The GPS NTP Server is Stratum-1. If it fails computer clocks will freewheel for hours or days before losing significant time, during which period you can simply order a replacement unit. If that isn’t fast enough, buy two $300 boxes. The “consensus” issue is moot, since a GPS server gets a consensus of clock time from the GPS satellite constellation.I guess you slept through GPS Week Roll Over day last April 6th? Some GPS went nuts, others did not. Many 777 and 787 were grounded that weekend for software updates to their expensive Honeywell GPS. I'll spare you the many more examples that hapened. Not nice when yoar clock rolls back to 1999, or forward to 2035. RGDS GARY --------------------------------------------------------------------------- Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703 gem () rellim com Tel:+1 541 382 8588 Veritas liberabit vos. -- Quid est veritas? "If you can’t measure it, you can’t improve it." - Lord Kelvin
Current thread:
- Re: NTP question, (continued)
- Re: NTP question Carsten Bormann (May 01)
- Building Integrated Timing System (was Re: NTP question) Sean Donelan (May 02)
- Re: NTP question Eric S. Raymond (May 06)
- Re: NTP question Carsten Bormann (May 01)
- Re: NTP question Ask Bjørn Hansen (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question Ask Bjørn Hansen (May 01)
- Re: NTP question Marco Davids via NANOG (May 02)
- Re: NTP question Harlan Stenn (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question Gary E. Miller (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question Gary E. Miller (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question Harlan Stenn (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question Gary E. Miller (May 01)
- Re: NTP question Mel Beckman (May 01)
- Re: NTP question William Herrin (May 02)
- Re: NTP question Mel Beckman (May 02)
- Re: NTP question Seth Mattinen (May 03)